What sentence patterns do these two sentences belong to and what do they describe, paving the way for the following lyricism?

These two sentences are antithetical sentences, describing the scenery on the shore and on the river. The willows on the shore are the scenery on the shore. Metaphor willow leafy. "Yiyi" describes the willows swaying in the wind and appearing light. Sha Ou on the river is the scenery on the river. Metaphor Sha Ou mostly stays by the river, and the river sand sets off its color bit by bit, paving the way for the feeling left by people later.

This sentence "Farewell to the Yellow Crane Tower" is a text in Book 9 of Jiangsu Education Press, and it is also the third text in Unit 7 of Book 1 of the fifth grade textbook of Jiangsu Education Press. It is an envelope poem, that is, it reproduces the creative situation of the ancient poem "Yellow Crane Tower Farewell Meng Haoran to Yangzhou" by Li Bai in the Tang Dynasty with vivid stories.

The lines of the whole poem are as follows:

Old friends frequently waved to me, bid farewell to the Yellow Crane Tower, and traveled to Yangzhou in this beautiful spring filled with catkins and flowers.

My friend's sail shadow faded away and disappeared at the end of the blue sky, only seeing the first line of the Yangtze River and heading for the distant horizon.

In the vernacular, my old friend waved to me frequently, bid farewell to the Yellow Crane Tower, and went on a long trip to Yangzhou on this catkin-like, flowery March spring day. The lonely sail shadow of my friend faded away and disappeared at the end of the blue sky, only seeing a line of the Yangtze River, heading for the distant sky.

Extended data

The lesson A Farewell to the Yellow Crane Tower is narrated in the order of events. The article mainly tells the story of Li Bai's farewell to Meng Haoran on the Yellow Crane Tower. This is a very common thing, but there are many extraordinary factors. First of all, it is located on the Yellow Crane Tower, one of the three famous buildings in the south of the Yangtze River. Because the Yellow Crane Tower is "overlooking the Yangtze River and climbing over the wall", the scenery is naturally unusual, and there are so many literati and poets.

Secondly, the characters are sent around by immortal poets. The feelings between poets are not necessarily nobler than ordinary people, but poets express these feelings through wonderful words.

Finally, it is the result of farewell. The most direct and precious result of the poet's emotional fluctuation is a well-known poem, and The Yellow Crane Tower Farewell to Meng Haoran in Yangzhou is a work that can stand any scrutiny among many farewell poems, which naturally makes this farewell poem look extraordinary.